[Boatanchors] teletype - I used a model 15 as a printer with my Imsai in 1976.

[oldradio at comcast.net]

I used a model 15 as a printer with my Imsai in 1976.

I also use a 15 and 28 on my ham station. (RTTY)

I wrote a program in machine code that converted ASCII to Baudot.  It intercepted a number character and sent an upshift, where it remained in upshift until the next letter character came along and downshifted again, and stayed there until it saw another number, etc.

Fed it to a Processor Technology 3P+S card which supplied a 20 MA output.  That drove a bi-polar relay which was in the 60 MA loop.

Worked like a champ, but at 60 wpm.  I was the only one in my group of friends who could print.  I shared my program with several ham friends who had a model 15 and an 8080 computer.

The reason for this, only commercial printers were available at $2000 to 4000.  Nothing cheap like today.  And I had an extra model 15.

My first commercial printer, the next year, was a Texas Instrument TI-810, which cost over $2000 and had a 7x5 matrix with no descenders on 'y' or 'g', etc.  But it was fast.

Those were the days!

73, John Dilks, K2TQN 
www.k2tqn.com/ 
Former Editor Vintage Radio Column, QST 2000-2014 
Having fun smelling hot rosin and solder again 


----- Original Message -----
That reminds me, some day I need to find a model 15  TTY so that I can get 
my first computer up and going again.
It is down  stairs and perhaps may still work if the old eproms are still  
good.
All wire wrapped. 
73
Bill  wa4lav

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